RESUMO
BACKGROUND: The genetics of sporadic and non-syndromic familial colorectal cancer (CRC) is not well defined. However, genetic factors that promote the development of precursor lesions, i.e. adenomas, might also predispose to CRC. Recently, an association of colorectal adenoma with two variants (c.507C>T;p.L169L and c.511G>T;p.A171S) of the ileal sodium dependent bile acid transporter gene (SLC10A2) has been reported. Here, we reconstructed haplotypes of the SLC10A2 gene locus and tested for association with non-syndromic familial and sporadic CRC compared to 'hyper-normal' controls who displayed no colorectal polyps on screening colonoscopy. METHODS: We included 150 patients with sporadic CRC, 93 patients with familial CRC but exclusion of familial adenomatous polyposis and Lynch's syndrome, and 204 'hyper-normal' controls. Haplotype-tagging SLC10A2 gene variants were identified in the Hapmap database and genotyped using PCR-based 5' exonuclease assays with fluorescent dye-labelled probes. Haplotypes were reconstructed using the PHASE algorithm. Association testing was performed with both SNPs and reconstructed haplotypes. RESULTS: Minor allele frequencies of all SLC10A2 polymorphisms are within previously reported ranges, and no deviations from Hardy-Weinberg equilibrium are observed. However, we found no association with any of the SLC10A2 haplotypes with sporadic or familial CRC in our samples (all P values > 0.05). CONCLUSION: Common variants of the SLC10A2 gene are not associated with sporadic or familial CRC. Hence, albeit this gene might be associated with early stages of colorectal neoplasia, it appears not to represent a major risk factor for progression to CRC.
Assuntos
Neoplasias Colorretais/genética , Predisposição Genética para Doença , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Simportadores/genética , Adulto , Idoso , Estudos de Casos e Controles , Neoplasias Colorretais Hereditárias sem Polipose/genética , Feminino , Frequência do Gene , Genótipo , Alemanha , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos ProspectivosRESUMO
INTRODUCTION: About 20% of colorectal cancer (CRC) patients show some kind of familiarity, which might be caused by yet unknown combinations of low penetrance susceptibility genes. We aimed to identify genetic factors for familial CRC (fCRC) in a unique study design that includes phenotypic extremes as represented by fCRC cases and 'hyper-normal' controls without CRC history and no adenomatous polyps on colonoscopy. MATERIALS AND METHODS: Candidate gene variants were determined by allele-specific amplification (SLC10A2 c.169C>T and c.171G>T) and restriction fragment length polymorphism assays (CCND1 c.870A>G; CDH1 -160C>A; TP53 R72P; VDR T2M). In total, 98 patients with fCRC, 96 patients with sporadic CRC, and 220 hyper-normal controls were included. RESULTS: The minor allele of the CDH1 -160C>A polymorphism occurred significantly more often in controls compared to fCRC cases (OR = 0.664; p = 0.042). Homozygosity of the minor allele was significantly associated with affiliation to the control group (OR = 0.577; p = 0.029), indicating that both heterozygous and homozygous carriers of the common allele are at-risk for CRC. With respect to the CCND1 c.870A>G mutation, comparison of fCRC and sporadic CRC cases showed that A/A homozygosity was more common than G/G homozygosity among fCRC patients compared to controls (OR = 2.119; p = 0.045). However, no differences in allele or genotype frequencies were detected between sporadic CRC cases and controls, and no associations were observed for SLC10A2, TP53, and VDR polymorphisms. CONCLUSIONS: We report a potential association of variants in the CCND1 and CDH1 genes with fCRC using a unique study design with phenotypic extremes.
Assuntos
Caderinas/genética , Neoplasias Colorretais/genética , Ciclina D1/genética , Regulação Neoplásica da Expressão Gênica , Polimorfismo Genético , Adulto , Idoso , Antígenos CD , Estudos de Casos e Controles , Colonoscopia , Neoplasias Colorretais/patologia , Feminino , Frequência do Gene , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Linhagem , Fenótipo , Regiões Promotoras Genéticas , Estudos Prospectivos , Medição de RiscoRESUMO
Abdominal infections are life-threatening complications in neutropenic patients. Among these, neutropenic cholecystitis is relatively rare. Nevertheless, its actual relevance is only investigated by anecdotal reports. We present a consecutive retrospective series of nine patients over a 12-year period. We calculated a frequency of 0.4% among all neutropenic episodes in patients with acute leukemia or aggressive lymphoma undergoing myelosuppressive chemotherapy. Only three of these patients had gallstones. Four patients died during the course of cholecystitis but in none of them cholecystitis was the primary cause of death. Systematic review of the literature revealed 45 patients with neutropenic cholecystitis of whom 26.7% died.
